JPH04311044A - Wire bonding device - Google Patents

Abstract

PURPOSE:To clean impurities adhering on substrates prior to a wire bonding to the substrates. CONSTITUTION:A plasma cleaning device 2 is provided between a stocker 1 for substrates 10 and a wire bonder 3, whereby the substrates 10 sent out from the stocker 1 are subjected to plasma cleaning and after impurities adhering on these substrates 10 are removed, the substrates 10 are transferred to the bonder 3 and a wire bonding is excellently performed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire bonding apparatus, in which a substrate sent out from a stocker is cleaned by a plasma cleaning apparatus and then wire bonded.

0002

2. Description of the Related Art In the manufacturing process of semiconductor devices, electrodes of a semiconductor mounted on a substrate are connected to electrodes of the substrate using wires. In such a wire bonding process, if impurities adhere to the electrodes of the substrate, the wires cannot be bonded to the electrodes well. These impurities include hand oils that adhere when a worker handles the substrate with his/her hands, gasified oil floating in the air, resist residue, and the like.

[0003] Ultrasonic cleaning has conventionally been used as a means to remove such impurities prior to wire bonding. Ultrasonic cleaning is a method of immersing a substrate in a cleaning liquid such as pure water and applying ultrasonic waves to the cleaning liquid to remove impurities.

0004

[Problems to be Solved by the Invention] However, the ultrasonic cleaning method requires the substrate to be dried by blowing hot air afterwards, which requires time and effort, and when it is dried, the cleaning liquid becomes a stain. There have been problems such as the fact that it tends to remain on the surface of the substrate.

SUMMARY OF THE INVENTION An object of the present invention is to provide a means that can solve the problems of the conventional means.

[0006]

[Means for Solving the Problems] The present invention provides a substrate stocker, a wire bonder for connecting the substrate and a semiconductor mounted on the substrate with a wire, and a wire bonder disposed between the stocker and the wire bonder. The plasma cleaning device includes a vacuum casing that can be opened and closed, a power supply unit that applies voltage to the vacuum casing to generate plasma, and a substrate supporting means provided inside the vacuum casing. A wire bonding apparatus is constructed by providing a feeding means for feeding the substrates of the stocker to the supporting means, and a conveying means for conveying the substrates on the supporting means to the wire bonder side.

[0007]

[Operation] In the above structure, the substrate is sent from the stocker to the support means with the vacuum casing open, and then the vacuum casing is closed. Next, a high voltage is applied to the vacuum casing to generate plasma inside the vacuum casing, and impurities adhering to the substrate are removed.

The vacuum casing is then opened and the substrate is sent to a wire bonder for wire bonding.

[0009]

Embodiments Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an overall side view of the wire bonding apparatus. This wire bonding apparatus includes a stocker 1 for substrates 10 such as lead frames, a plasma cleaning device 2, and a wire bonder 3 arranged side by side. A semiconductor P is mounted on the substrate 10.

[0011] In the stocker 1, substrates 10 are stored in stacks. 4 is a support plate for the stocker 1,
Nut 5 is attached. A ball screw 6 is screwed into this nut 5. M1 is a motor that rotates the ball screw 6.

A cylinder 7 is provided behind the stocker 1 as a feeding means. Drive the motor M1 to raise and lower the stocker 1 and move the substrate 10 into the cylinder 7.
When the rod 8 is positioned in front of the rod 8 and the rod 8 protrudes, the substrate 10 is pushed forward.

The plasma cleaning device 2 mainly includes a vacuum casing 11 consisting of an upper case 11a and a lower case 11b. The upper case 11a is supported by a rod 13 of the cylinder 12, and when the rod 13 protrudes and retracts, the upper case 11a moves up and down, and the casing 11 opens and closes. The upper case 11a and the lower case 11b are grounded by a ground portion 14.

[0014] Inside the casing 11, a support means 15 for the substrate 10 is provided. This support means 15 also serves as a cathode, and a high voltage is applied by a power supply section 16. A heater 17 is embedded in this support means 15, and heats the substrate 10 prior to wire bonding. In this way, the substrate 10 is placed in the plasma cleaning device 2.
By providing the heater 17, which is a heating means, the substrate 10 can be preheated in a convenient manner prior to wire bonding.

18 is a suction pipe, 19 is a valve, and 28 is a pump, which sucks the gas inside the casing 11,
Vacuum the casing 11. 26 and 27 are pipes and valves for returning the casing 11 to normal pressure. 20 is an air supply pipe, 21 is a valve, and A is supplied from this pipe 20 into the casing 11 as a plasma discharge gas.
An inert gas such as r gas is supplied.

The wire bonder 3 consists of a guide means 21 for the substrate 10 and a bonding means 22 provided above the guide means 21. Bonding means 2
2 includes a horn 23 and a capillary tool 24 held by the horn 23, and a wire 25 inserted through the capillary tool 24 connects the semiconductor P on the substrate 10 and the substrate 10. The guide means 21 are provided at the same level as the support means 15.

FIG. 2 is a plan view of a conveyance means for conveying the substrate 10 on the support means 15 to the wire bonder 3 side. 3
0 is an arm-shaped pusher, and a ball screw 32 in the X direction is screwed into a nut 31. 33 is ball screw 3
This is a motor that drives 2.

The motor 33 is supported by a nut 34. 35 is a Y-direction ball screw screwed into this nut 34, and 36 is a motor.

When the motor 33 is driven and the ball screw 32 rotates, the nut 31 slides along the ball screw 32 in the X direction, and the pusher 30 also slides in the same direction. Further, when the motor 36 is driven, the nut 34 slides in the Y direction along the ball screw 35, and the pusher 30 also slides in the same direction. 37 is a guide portion of the substrate 10 provided on the support means 15. In this way, move the pusher 30 in
By moving the substrate 1 on the support means 15 in the direction
0 to the wire bonder 3 side.

The present apparatus has the above-mentioned configuration, and its operation will be explained next. With the upper case 11a open, the rod 8 of the cylinder 7 protrudes, so that the substrate 10 of the stocker 1 is sent onto the support means 15 inside the casing 11. Then, the upper case 11a is closed, and the casing 11
There is a vacuum inside. Furthermore, inert gas is sent from the pipe 20, and then high frequency and high voltage is applied to the support means 15, thereby generating plasma.

At the same time, a portion of the inert gas is ionized, and the ions move violently and at high speed within the casing 11, collide with the surface of the substrate 10, and remove impurities adhering to this surface. The removed impurities are removed by suction by the pump 28.

After cleaning the substrate 10 in this way, the valve 27 is opened to release the vacuum state and return the inside of the casing 11 to normal pressure.

Next, the case 11a is raised to open the casing 11. Next, the motor 36 is driven to push the pusher 3
0 extends behind the substrate 10 on the support means 15 (see the chain line in FIG. 2), and then the motor 33 is driven and the pusher 30 moves forward, so that the substrate 10 is moved onto the guide means 21 of the wire bonder 3. (See the broken line in Figure 2).

Next, wire bonding is performed while the capillary tool 24 moves in the X and Y directions. In this case, since the substrate 10 has been plasma cleaned to remove impurities, wire bonding can be performed satisfactorily.

The present invention is not limited to the above-described embodiment; for example, opening and closing doors may be provided on the front and rear surfaces of the vacuum casing, and the substrate 10 may be taken in and taken out by opening and closing the opening and closing doors.

[0026]

[Effects of the Invention] As explained above, the present invention provides a substrate stocker, a wire bonder that connects the substrate and a semiconductor mounted on the substrate with a wire, and a wire bonder disposed between the stocker and the wire bonder. This plasma cleaning device is equipped with a vacuum casing that can be opened and closed, a power supply unit that applies voltage to the vacuum casing to generate plasma, and a substrate support provided inside the vacuum casing. The wire bonding apparatus comprises a feeding means for feeding the substrate of the stocker to the supporting means, and a conveying means for conveying the substrate on the supporting means to the wire bonder side. Prior to the bonding process, impurities adhering to the substrate can be removed cleanly and with good workability, and wire bonding can be performed satisfactorily.

[Brief explanation of the drawing]

FIG. 1: Overall side view of a wire bonding device according to the present invention.

[Fig. 2] A plan view of the conveying means according to the present invention.

[Explanation of symbols]

1 Stocker 2 Plasma cleaning device 3 Wire bonder 7 Cylinder 10　Substrate 11 Casing 15 Support means 16 Power supply section 30 Pushko

Claims (1)

[Claims] Claim 1: A substrate stocker, a wire bonder for connecting the substrate and a semiconductor mounted on the substrate with a wire, and a plasma cleaning device disposed between the stocker and the wire bonder. The plasma cleaning device has a vacuum casing that can be opened and closed,
It consists of a power supply unit that applies a voltage to the vacuum casing to generate plasma, a substrate support means provided inside the vacuum casing, and a delivery device that sends out the substrates of the stocker to the support means; A wire bonding apparatus comprising a conveyance means for conveying the substrate on the support means to the wire bonder side.